04 Recon ES completly stock with 300 MI cutting out/missing at 2/3 throttle and above. The bike is hard starting when cold as are most of them but did not notice the problem until my daughter drag raced her sister on an 05 Ozark and lost badly. Prior to this the Recon would stay even in this situation and win when a shift was missed on the Ozark. I took the Recon to the dealer they say they could find nothing wrong, looked through the forum postings and checked the following. Carb removed cleaned and checked, no dirt in the float bowl all jets open. Had an extra wireing harness from e-Bay and tried changing coil pack and ignition module with no improvement. One strange thing, my Honda Manual had two possible parts diagrams for the assembly of the air valve on the carb. One shows the spring under the diaphram and two show it on top of the diaphram, I went with spring on top.
The bike has plenty of response at the low end but when you try to wind her out in any gear it sounds like a valve float once you get to 2/3 throttle. I don't believe I am hitting the rev limiter because I had ridden the bike before, shifting when the RPM and speed felt right without the lost lamb sound and cutting out. If anyone out there has had this problem please let me know because my Honda driver does not like getting beat by the Ozark and hearing the Honda junk talk.

 

Itll be a carb problem, this one has no throttle position sensor, so the motor doesnt know the throttle setting.
Is the needle jet loose? It should wiggle a bit, but it shouldnt be free to go up and down in the hole, in the slide.
If you pull the choke on, while its sputtering...does it get better or worse?
Welcome to the forums

 

The needle valve or jet does move up and down a little, about 1/16 of an inch as there is white plastic keeper and a very small spring above the jet. I have not tried to play with the choke above 2/3 throttle when the engine cuts out but I will. I noticed that there was no adjustment to the float level on this carb but the float was not broken or leaking, no dirt in the float bowl either. I ran the engine without the air cleaner and blew out the spark arrestor by removeing the drain plug, no change. Any thoughts on the air valve spring? does it go on top or the bottom of the rubber diaphragm. My Honda service manual shows it both.

 

Seems to me , this is a slide carb, and not a cv carb, so im not sure which diapham is in there, maybe they mean the plate.
If you click on the ronnies banner, above, and go to the parts finder, and look up the 04 recon, and click on carb (maybe this link will work)here
It looks like the spring holds down #13, the so called plate. It should also help keep the needle in place too.

Running with the air lid off, will make it very lean, and itll give you symptoms like you have. If you put the lid back on, does it still run crappy?

Is everything else stock? How long since the spark plug was changed?

 

The diaphragm is in the air cut off valve on top of the carb, it has three vacuum hoses coming out of it. Ronnies shows the valve but not disassembled. Running with the air lid off made no difference in the cutting out at 2/3 throttle and above. Started the bike let it warm up then tried puling the choke in and out while it was cutting out and made no difference until almost all the way out then it started to die. The bike has 314.42 miles on it, have a Trail Tech speedo installed, it was a left over 04 purchased on 2/27/05. Checked the plug and it was clean with a grey white color at the tip. The plug body at the end of the threads did show some light carbon deposit.

Called my local Bike Repair Shop (Super Daves) who has been in business for a long time here in this quad heaven area to see if my Honda Extended warrenty was accepted there. He said that he believed that there was a rev limiter built into the CDI box. As I mentioned I tried a known good CDI from an e-bay purchase and it made no difference, it still cut out at 2/3 throttle and above.

Any other Recon ES owners out there that have the same experience or is it just our machine.

 

When mine was doing that it ended up been the throttle cable. I used some wd-40 under the throttle cover and under the carb cap. Took awhile to figure it out no problems since.